1-Cyclopropyl-8-methyl-7-[5-methyl-6-(methylamino)-3-pyridinyl]-4-oxo-1,4-dihydro-3-quinolinecarboxylic acid is disclosed in U.S. Pat. No. 6,335,447. This substance is known under its International Nonproprietary Name of ozenoxacin. Its chemical formula is:

Ozenoxacin is a known antibacterial agent. Some dermal compositions comprising ozenoxacin have been disclosed in JP2002356426A, JP2003226643A, EP1731138A1, and WO2007015453A1. Ophthalmic compositions of ozenoxacin have been disclosed in JP2007119456A, and Yamakawa, T. et al., Journal of Controlled Release (2003), 86(1), 101-103.
The above referenced U.S. Pat. No. 6,335,447 generically refers to salts but does not disclose any specific salt of the des-fluoroquinolone compounds (I).
In the FT-Raman spectra the axis of the ordinates shows intensity and the axis of the abscissas shows the Raman shift (cm−1).
In the IR spectrum the axis of the ordinates shows percentage of absorption and the axis of the abscissas shows the wavelength (cm−1).
In the powder X-ray diffraction patterns the axis of the ordinates shows the diffraction intensity and the axis of the abscissas shows the diffraction angle (28).